YOU SAID:
I play the guitar, do you?
INTO JAPANESE
ギターを弾きますか?
BACK INTO ENGLISH
Do you play guitar?
INTO JAPANESE
ギターを弾いていますか?
BACK INTO ENGLISH
Are you playing guitar?
INTO JAPANESE
ギターを弾いていますか?
BACK INTO ENGLISH
Are you playing guitar?
That didn't even make that much sense in English.